Totally disconnected space: Difference between revisions

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The [[rational numbers]] form a totally disconnected space. In fact, any irrational number gives a ''disconnection'' by partitioning the rational numbers into two open subsets -- the subset of numbers less than the given irrational and the subset of numbers greater than the given irrational.
The [[rational numbers]] form a totally disconnected space. In fact, any irrational number gives a ''disconnection'' by partitioning the rational numbers into two open subsets -- the subset of numbers less than the given irrational and the subset of numbers greater than the given irrational.
==References==
===Textbook references===
* {{booklink|Munkres}}, Page 152, Exercise 5 (definition introduced in exercise)

Revision as of 22:30, 21 April 2008

This article defines a property of topological spaces: a property that can be evaluated to true/false for any topological space|View a complete list of properties of topological spaces

This is an opposite of connectedness

Definition

A topological space is said to be totally disconnected if its connected components are one-point sets.

Relation with other properties

Stronger properties

Examples

The rational numbers form a totally disconnected space. In fact, any irrational number gives a disconnection by partitioning the rational numbers into two open subsets -- the subset of numbers less than the given irrational and the subset of numbers greater than the given irrational.

References

Textbook references

  • Topology (2nd edition) by James R. MunkresMore info, Page 152, Exercise 5 (definition introduced in exercise)